Front engine attachment system intended for an aircraft engine and having a compact structure

Abstract

A system for attaching a front engine of an aircraft, having: a vertical median plane, an engine pylon with a nose having a main female clevis, and a cylindrical housing around a vertical axis, a main link fastened to a front casing of the engine by a secondary ball-joint connection about a secondary axis perpendicular to the median plane by a secondary shaft, a main shaft, perpendicular to the median plane and forming a main ball-joint connection of the main link in the main female clevis about a main axis, the main and secondary axes in the plane perpendicular to the median plane, and an outer cylinder, coaxial with the vertical axis and a first end of which fastened in the cylindrical housing and a second end of which mounted, via an annular linear connection, around the vertical axis with respect to the front casing.

The invention claimed is: 
     
         1 . A front engine attachment system for an engine of an aircraft, the front engine attachment system having a vertical median plane, where the vertical median plane is an XZ plane in a coordinate system where X denotes a longitudinal direction of the engine with positive orientation in the direction of forward movement of the aircraft, Y denotes a transverse direction of the engine, and Z denotes a vertical direction of the engine and comprising:
 an engine pylon having, at a front part, a nose having a main female clevis, and a cylindrical housing around a vertical axis,   a main link configured to be fastened to a front casing of the engine by a secondary ball-joint connection about a secondary axis perpendicular to the vertical median plane by a secondary shaft,   a main shaft, which is perpendicular to the vertical median plane and which forms a main ball-joint connection of the main link in the main female clevis about a main axis, wherein the main axis and the secondary axis are in the same vertical plane perpendicular to the vertical median plane, and   an outer cylinder, which is coaxial with the vertical axis and a first end of which is fastened in the cylindrical housing and a second end of which is configured to be mounted, via an annular linear connection, around the vertical axis with respect to the front casing.   
     
     
         2 . The front engine attachment system according to  claim 1 , wherein a location of the main axis is arranged in front of a location of the vertical axis. 
     
     
         3 . The front engine attachment system according to  claim 1 , wherein the main link is configured to be fastened to a second female clevis of the front casing by a pivot connection about a pivot axis perpendicular to the vertical median plane,
 wherein the front engine attachment system further comprises a second shaft forming the pivot connection, and   wherein the second shaft is mounted with clearance in a bore in the main link and configured to be mounted with a tight fit in bores in the second female clevis.   
     
     
         4 . The front engine attachment system according to  claim 1 , wherein the nose has two lateral stops, which are arranged respectively on a port side and on a starboard side of the outer cylinder and are configured to come between two lateral counter-stops of the front casing. 
     
     
         5 . The front engine attachment system according to  claim 1 , further comprising:
 two lateral links arranged respectively on a port side and on a starboard side of the main link, and   wherein each lateral link is mounted on the main shaft with a tight fit and on the secondary shaft with clearance.   
     
     
         6 . The front engine attachment system according to  claim 1 , wherein the main shaft comprises a peripheral shaft, which is hollow, and an inner shaft, which is housed in the peripheral shaft. 
     
     
         7 . An aircraft comprising:
 a structure,   an engine with a front casing,   the front engine attachment system according to  claim 1 , wherein the main link is fastened to the front casing by the secondary ball-joint connection, and   wherein the second end of the outer cylinder is mounted, via the annular linear connection, around the vertical axis with respect to the front casing.